. "True confessions" continues. Here's nick watt. ? Reporter: You're packed inside a big dark room with a couple of hundred total strangers. What's that smell? What's that guy doing? What's that on my foot? Is that legal? That can't be clean. We are on a journey, swabbing theaters across the land and grilling the experts. There's nothing more crazy than owning a movie theater. Reporter: To bring you the truth -- There's no law that says they have to clean these seats. Yeah, that's disturbing. Reporter: What goes on inside the movie theater once the lights are down? Well, you can tell what goes on inside a movie theater with what you find after. Ok, go on. Used condoms. Really? Reporter: Have you ever caught somebody in the moment? Yes. But if nobody complains, let them get away with it. Reporter: What I always complain about are the prices, 8 bucks for a bucket of popcorn that costs, wait for it, maybe 8 cents to make? A 10,000% mark up. Seriously. Reporter: Daylight robbery? Well, not exactly. I make money by selling concessions. Reporter: Because, and here's a little-known fact, up to 70% of your ticket price goes to the studio and distributor, leaving the theatre owner with pocket change. Some theaters get paid to play those endless trailers you must endure before the main event. But they all need to sell a lot of concessions just to stay afloat. And wait until you hear this. You got to do little tricks to, to get them to buy concessions. Reporter: Okay, like? Well, in my theater, I've a exhaust pipe that runs from the popcorn machine into the actual auditorium. They're going to have to come out and buy some popcorn. Reporter: You used to pipe the smell of popcorn into the auditorium? Oh no, we still do pipe the smell of popcorn into the auditorium. Absolutely. Sure, it smells good but you don't have to eat everything in front of you. So says the fat guy. Reporter: And if we dent all fall prey to the concession stand, our ticket prices would skyrocket. It's a nacho cheesy, hot diggity dog, trade off. But there is another problem with all that food. You spill something. And then just suddenly you're wearing it, right. I don't want to be that guy. You know, a lot of theaters have problems -- I don't want to say this. I won't say it. Reporter: Come on. I mean, let's say you -- you may have some little creatures running around your feet at night. Roaches or rodents. You walk around and your shoes stick to the floor. So, who's going to wear sandals? Or what's walking on you, bed bugs. Late last year there reports of itching at a theater in Wisconsin. And in 2010 the AMC empire in times square closed temporarily while exterminators culled some little critters. Remember I said we took samples we're going to go in and try swab the seats and the floor without anybody noticing. We did this in a bunch of theaters in New York and los Angeles and we came back to Dr. Philip Tierno to analyze our results. The seat and other areas of the theater are contaminated with the public that sat before you. Reporter: On theater seats, armrests and even 3-d glasses sealed in plastic. We found traces of all kinds of live organisms with big, scary names microscopic bugs that can cause things like food poisoning boils and sinusitis. In a Manhattan cinema we detected bacteria usually found in cattle and soil. Don't ask me. On seats in both L.A. And new York, we found bacteria common in human feces more understandable just as gross. Are there government laws as to how often you have to clean these chairs? No, unfortunately. There should be. Some theaters don't. I've been in theaters that -- that they don't -- they don't clean up. Reporter: Okay, doc, so help us out, how do we not get that stuff in our mouths? If you're going to hit the armrest keep your hand in the air so that you can go to the dirty hand, this one that can touch anything including the outside of the popcorn box, and then you eat your popcorn with your good hand. Always have a "Good hand" and a "Bad hand." Reporter: Micrococcus luteus on the armrest, you know what, that's almost forgivable. This is not. People who are texting while you're trying to watch the movie. You might as well bring a flashlight and shine it over your shoulder at the people behind you. Reporter: The Alamo drafthouse chain, which has a zero-tolerance cell phone policy, recently banned Madonna from all their theatres for allegedly texting during "12 years a slave." Until Madonna apologizes, she's not welcome at the Alamo drafthouse. Reporter: And listen to this voicemail left by another patron kicked out for a similar crime. I didn't know that I wasn't supposed to text in your little crappy ass theater. Seems like she maybe had a little bit too much to drink and gave us a piece of her mind. And it was very, uh, charming in its own way. You know what -- Reporter: The chain used this as a public service announcement before r-rated movies. So, excuse me, for using my phone in usa magnited states of America! They gotta go. Reporter: Robert bucksbaum, who remember, will never break up a courting couple will kick you out for cell phone use. You've got a stricter policy on cell phone use than you have on having sex in the theater? Absolutely. You know, if you're not bothering another customer, you get away with as much as you want in a movie theater. Reporter: And that's why, when all's said and done, going to the movies is the most fun you can have with your clothes on. Or off. Perhaps. If you're those kind of people. Tougher rules on your cell phones than on your clothes. Let's us what you think. When we come back -- who

This transcript has been automatically generated and may not be 100% accurate.

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